Tag: sun

Sunspot update October 2018: Deepening minimum

9:04 am

The monthly NOAA update of the solar cycle, covering sunspot activity for October 2018, was released yesterday. As I have done every month since this website began in July 2011, I am posting it below, annotated to give it some context.

Though there was a tiny uptick in sunspot activity on the Sun in October, the uptick was inconsequential. Overall, the activity in the past few months appears to closely match the weak activity seen in late 2007 and early 2008, just when the last solar minimum began.

October 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

As I noted in August, the NOAA graph is now getting very close to its right edge, which ends in December 2018. They will very soon have to update this graph so that it can take us into the next solar cycle. While they must do this, it will unfortunately end the standard visual used by them for more than a decade for showing the progress of the solar cycle. Depending on how they change it, I might be able adapt it to include this graph to allow a continuation of the same visual into the future. We will have to see.

Having seen now the full solar maximum for this cycle (weak and short), we are now moving to the next question: Will the developing solar minimum be as long and as deep as the last? Will it evolve into a grand minimum, lasting decades, as some solar scientists believe?

Or will the Sun return to the higher levels of activity seen during most of the 24 solar cycles observed since the last grand minimum in the 1600s?

Since our understanding of these changes is very poor, your guess is likely as good as anyone else’s. All we can really do is keep our eyes open and watch what happens.

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Parker begins first perihelion fly-by of Sun

9:10 am

It’s getting hot in here: The Parker Solar Probe has begun its first close orbital fly-by of the Sun, set to last from now until November 11.

This solar encounter encompasses the first perihelion of the mission, the point at which Parker Solar Probe is closest to the Sun. Perihelion is expected at about 10:28 p.m. EST on Nov. 5. The spacecraft will come within 15 million miles of the Sun’s surface and clock in at a top speed of 213,200 miles per hour relative to the Sun — setting new records for both closest solar approach and top heliocentric speed by a spacecraft. At perihelion, Parker Solar Probe will fly through material at about 3.6 million degrees Fahrenheit — but because material in this region is so tenuous, it doesn’t influence the temperature of the spacecraft. However, the Sun’s intense radiation heats the Sun-facing side of the spacecraft’s heat shield, called the Thermal Protection System, to about 820 F.

For several days around the Nov. 5 perihelion, Parker Solar Probe will be completely out of contact with Earth because of interference from the Sun’s overwhelming radio emissions.

The article provides some nice details about the spacecraft’s design.

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Parker sets new records in its flight to the Sun

9:19 am

The Parker Solar Probe has set two new space records, first for making the closest approach to the Sun as well as becoming the fastest spacecraft ever.

The spacecraft passed the current record of 26.55 million miles from the Sun’s surface on Oct. 29, 2018, at about 1:04 p.m. EDT, as calculated by the Parker Solar Probe team. The previous record for closest solar approach was set by the German-American Helios 2 spacecraft in April 1976. As the Parker Solar Probe mission progresses, the spacecraft will repeatedly break its own records, with a final close approach of 3.83 million miles from the Sun’s surface expected in 2024.

“It’s been just 78 days since Parker Solar Probe launched, and we’ve now come closer to our star than any other spacecraft in history,” said Project Manager Andy Driesman, from the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. “It’s a proud moment for the team, though we remain focused on our first solar encounter, which begins on Oct. 31.”

Parker Solar Probe is also expected to break the record for fastest spacecraft traveling relative to the Sun on Oct. 29 at about 10:54 p.m. EDT. The current record for heliocentric speed is 153,454 miles per hour, set by Helios 2 in April 1976.

We ain’t seen nothin’ yet. This is only the first orbit. With each later orbit the spacecraft will zip past the Sun faster, and closer.

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Parker looks back at Earth

8:51 am

Earth and Moon, taken by the Parker Solar Probe

The Parker Solar Probe, flying inward towards its first close fly-by of the Sun, has looked back at the Earth and snapped its picture.

The image was captured by the WISPR (Wide-field Imager for Solar Probe) instrument, which is the only imaging instrument on board Parker Solar Probe. During science phases, WISPR sees structures within the Sun’s atmosphere, the corona, before they pass over the spacecraft.

…Zooming in on Earth reveals a slight bulge on the right side: that is the Moon, just peeking out from behind Earth. At the time the image was taken, Parker Solar Probe was about 27 million miles from Earth.

The importance of this image is that it demonstrates that the spacecraft’s camera is working properly, and that the spacecraft itself can point accurately.

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Sunspot update September 2018: Minimum!

9:58 am

NOAA yesterday released its monthly update of the solar cycle, covering sunspot activity for September 2018. As I have done every month since this website began in July 2011, I am posting it below, annotated to give it some context.

Sunspot activity on the Sun in September dropped slightly from August. More significantly, the activity continues to match closely the weak activity seen in 2008, when the Sun last went through its last solar minimum. We are unquestionably now in the new minimum, and its arrival in the past few months makes the now-ending solar cycle about one to two years shorter than predicted.

September 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

As I noted last month, the NOAA graph is now getting very close to its right edge, which ends in December 2019. They will very soon have to update this graph so that it can take us into the next solar cycle.

What that new cycle will bring will be the next mystery. I have been following this cycle now since its unusual beginning, with a solar minimum much much longer and more inactive than any solar scientist had ever expected. We can only guess at the surprises the Sun will give us in the coming decade, especially since the science of solar sunspot activity remains superficial and in its infancy. We do not really understand why the Sun’s activity fluctuates. Nor do we understand why it periodically stops producing sunspots for long periods, resulting in what solar scientists call a grand minimum.

There are some scientists who think another grand minimum is coming. We shall have to wait and see. I certainly am going to follow their upcoming observations, as this work remains one of the great scientific studies humans are presently pursuing.

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Data from Voyager 2 suggests it is entering interstellar space

7:50 pm

New data since August from Voyager 2 now suggests it is finally leaving the heliosphere of the solar system and entering interstellar space.

Since late August, the Cosmic Ray Subsystem instrument on Voyager 2 has measured about a 5 percent increase in the rate of cosmic rays hitting the spacecraft compared to early August. The probe’s Low-Energy Charged Particle instrument has detected a similar increase in higher-energy cosmic rays.

Cosmic rays are fast-moving particles that originate outside the solar system. Some of these cosmic rays are blocked by the heliosphere, so mission planners expect that Voyager 2 will measure an increase in the rate of cosmic rays as it approaches and crosses the boundary of the heliosphere.

In May 2012, Voyager 1 experienced an increase in the rate of cosmic rays similar to what Voyager 2 is now detecting. That was about three months before Voyager 1 crossed the heliopause and entered interstellar space.

The scientists warn that there is great uncertainty here, and that the actual transition into interstellar space might take longer than with Voyager 1 since Voyager 2 is traveling in a different direction and is leaving during a different time in the solar cycle.

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All instruments check out on the Parker Solar Probe

9:24 am

The initial check out of the Parker Solar Probe, now on its way to the Sun, has shown all instruments are functioning properly.

“All instruments returned data that not only serves for calibration, but also captures glimpses of what we expect them to measure near the Sun to solve the mysteries of the solar atmosphere, the corona,” said Nour Raouafi, Parker Solar Probe project scientist at the Johns Hopkins University Applied Physics Lab in Laurel, Maryland.

The mission’s first close approach to the Sun will be in November 2018, but even now, the instruments are able to gather measurements of what’s happening in the solar wind closer to Earth.

The spacecraft will make its first fly-by of Venus in October.

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Update on the Parker Solar Probe

8:49 am

Link here. The press release notes that the spacecraft’s instruments are one by one being made operational without problem and that it has also successfully completed a second course adjustment.

The release also provided a link to a page which will shows the probe’s present location. This is useful, as it also shows the probe’s position in relation to the Sun, Venus, and the Earth.

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Sunspot update for August 2018: The slide to minimum

12:28 pm

As it does the first Sunday of each month, yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for August 2018. And as I do every month, I am posting it below, annotated to give it some context.

The Sun in August had a slight uptick in sunspot activity, but not a very significant one. As such, the slide to solar minimum continues. Right now the lack of sunspot activity in 2018 is heading to match or even exceed 2007, the year in which the previous solar minimum began.

August 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

If you look at the original graph at NOAA, you will see that we are getting very close to the right edge of the graph. I expect that sometime in the next few months NOAA will update the graph, a necessary act that will in one sense be a shame, as they have been adding monthly updates to this graph since the beginning of the last solar minimum. This has allowed everyone to see a standard visual, month to month, for comparing solar activity. It has also allowed me to annotate the graph properly to show how the 2007 and 2009 predictions held up against actual activity. Once the graph changes it will be more difficult to do this.

Anyway, it is very clear we are entering solar minimum, and that the solar cycle we are now completing will be both a short and weak cycle. What happens next is really the big question. Will the Sun sunspot activity recover? Or will we enter the first grand minimum since the 1600s? Either way, for solar scientists the coming years are going to be very exciting.

Posted on interstate 10 going from Tucson to Phoenix, on the way to the wooded northern forests of Arizona, where Diane and I will spend a couple of days visiting friends at their upstate cabin/home.

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Parker makes first course adjustment

9:29 am

The Parker Solar Probe successfully made its first mid-course correction burn yesterday.

Spacecraft controllers at the mission operation center initiated the two-part TCM-1 [trajectory correction maneuver] beginning at 6:00 a.m. EDT on Aug. 19 with a 44-second burn of the engines. The majority of the engine firing, which lasted just over seven minutes, began at 6:00 a.m. EDT on Aug. 20.

The spacecraft is now traveling at almost forty thousand miles per hour, easily enough to escape the solar system. Its course however is such that it will instead zip past the Sun, at closer distances after each orbit and Venus flyby.

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Sunspot update for July 2018: The Sun flatlines!

10:50 am

Yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for July 2018. As I do every month, I am posting it below, annotated to give it some context.

This might be the most significant month of solar activity that has been observed since Galileo. Except for two very short-lived and very weak sunspots that observers hardly noted, the Sun was blank for entire month of July. This has not happened since 2009, during the height of the last solar minimum.

What makes this so significant and unique is that it almost certainly signals the return of the next solar minimum, a return that comes more than a year early. The solar cycle the Sun is now completing has only been ten years long. It is also one of the weakest in more than a hundred years. This combination is unprecedented. In the past such a weak cycle required a long cycle, not a short one.
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Sunspot update for June 2018: Activity increases again

5:56 pm

NOAA today posted its monthly update of the solar cycle, covering sunspot activity for June 2018. Below is this month’s annotated graph.

For the third straight month the Sun showed a small increase in sunspot activity. The pattern also continued to follow the two-week-on/two-week-off pattern of activity caused by the Sun’s 27-day rotation, as I described in my update last month.

June 2018 sunspot activity

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction. The yellow line compares the present activity with the activity during solar minimum in 2008 and 2009.

This pattern is continuing. As of today, there have been no sunspots since June 28, almost two weeks. I would not be surprised if some sunspots appeared within the next week, especially because today’s image of the Sun from Solar Dynamic Observatory shows bright faculae rotating into view. Faculae are, like sunspots, a sign of solar magnetic activity. The two usually go together.

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Sunspot update for April 2018: Heading into solar minimum

9:00 am

On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for April 2018. Below is my annotated version of that graph.

While there was an uptick in sunspots in April, compared to the almost complete inactivity in March (the least active month for sunspots in a decade), the uptick did little to change the general trend. Sunspot activity is now comparable to what we saw in early 2008 (as indicated by the yellow line). This was just before the arrival of the previous solar minimum, which happened to also be one of the longest and deepest on record.

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Issue with thermometers on Parker Solar Probe

8:56 am

As NASA prepares the Parker Solar Probe for its summer launch, engineers are reviewing an issue with the spacecraft’s thermometers.

As those preparations continue, officials are studying problems with devices known as platinum resistance thermometers that are part of the spacecraft’s thermal control system. Those devices have suffered a higher-than-expected failure rate, according to a presentation at an April 5 meeting of NASA’s Heliophysics Advisory Committee.

The thermometers are lightweight, highly sensitive temperature sensors used to help provide feedback to the spacecraft’s cooling system and solar arrays, NASA spokesman Dwayne Brown said April 9. “We put all spacecraft through a rigorous test program to make sure all systems are working as designed and it is normal for a test program to uncover issues.”

“The team is looking very carefully at whether any change is needed,” Peg Luce, acting director of NASA’s heliophysics division, said at the meeting. The issue, she said, was debated “quite significantly” at a review last week to approve the shipment of the spacecraft to Florida, including whether to delay that shipment to study the problem. “There are certain, possible fixes if we need to fix something that could be done at the Cape, so the decision was to go ahead and ship,” she said.

This issue is especially critical as the spacecraft is intended to fly as close as four million miles from the Sun. If these thermometers fail too easily, the spacecraft will not be able to monitor its temperature properly, and it will likely fail much sooner than planned.

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Sunspot update for March 2018: the sun crashes!

11:49 am

It surely looks like the solar minimum has arrived, and it has done so far earlier than expected! On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for March 2018. Below is my annotated version of that graph.

March 2018 was the least active month for sunspots since the middle of 2009, almost nine years ago. In fact, activity in the past few months has been so low it matches the low activity seen in late 2007 and early 2008, ten years ago when the last solar minimum began and indicated by the yellow line that I have added to the graph below. If the solar minimum has actually arrived now, this would make this cycle only ten years long, one of the shortest solar cycles on record. More important, it is a weak cycle. In the past, all short cycles were active cycles. This is the first time we have seen a short and weak cycle since scientists began tracking the solar cycle in the 1700s, following the last grand minimum in the 1600s when there were almost no sunspots.
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Sunspot update for February 2018

12:25 pm

It’s time for my monthly sunspot update. On Sunday NOAA posted its monthly update of the solar cycle, covering sunspot activity for February 2018. Below the fold is my annotated version of that graph.

Sunspot activity in February continued the low activity seen in November, December, and January, with November 2017 still the most inactive month for sunspots since the middle of 2009. In fact, the low activity we are seeing now is somewhat comparable to the low activity seen during the ramp down to solar minimum in the first half of 2008. By the end of that year we had hit solar minimum, the deepest and longest in a hundred years, suggesting that we might even hit solar minimum before the end of this year. That would have this happen at least a year earlier than all predictions.
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Sunspot update for January 2018

11:51 pm

Today NOAA posted its monthly update of the solar cycle, covering sunspot activity for January 2018. Below is my annotated version of that graph.

As you can see, the low sunspot activity of the past two months continued in January. November 2017 remains the most inactive month for sunspots since the middle of 2009. January is now the second most inactive month, with December a very close third.

January 2018 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Though activity continues to track close to but considerably below the 2007 weak prediction, the difference appears to be increasing as the ramp down to solar minimum continues. While I have said in past updates that the trend suggests an early arrival of the solar minimum, a close look at the previous ramp down in 2007 and 2008 shows that when activity became this weak, the ramp down slowed considerably. This previous pattern suggests that we could see another year or two of similarly low activity before the minimum arrives.

Regardless, the low activity, this soon, continues to suggest that the next maximum will also be weak, and might even not come at all, as some solar scientists have proposed. Instead, we might be heading toward another Grand Minimum, with no significant sunspots for decades.

Will that Grand Minimum produce cold weather worldwide, as it appears to have done during the last Grand Minimum in the 1600s? There is circumstantial evidence in the past decade that it might. We will not know, however, until it happens, and that possibility remains very uncertain.

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The Sun goes quiet! Sunspot update for November 2017

11:51 am

The past month was the most inactive month for sunspots since the middle of 2009, when the last solar minimum was just ending and the Sun was beginning its ramp up to solar maximum.

NOAA on Sunday posted its monthly update of the solar cycle, covering sunspot activity for November. As I have done every month since 2010, I have posted that graph below, with annotations.

November 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

I have also added a straight yellow line near the bottom of the graph, indicating how the lack of activity this past month corresponds with the lack of activity in the summer of 2009, just when that unusually long and deep solar minimum was beginning to end.

November 2017 sunspot record

To get an idea how few sunspots were seen in November, the graph on the right, produced by SILSO (Sunspot Index and Long-term Solar Observations) on December 1, shows only 10 days during the entire month when any sunspots were active on the Sun’s visible hemisphere. And even those sunspot were few and weak, resulting in tiny sunspot numbers total.

Nor is December looking any different, with no sunspots recorded so far, four days into the month.

The plunge to solar minimum continues to appear to be happening faster than normal. At this pace, solar minimum will arrive in early 2018, making this one of the shortest solar cycles on record. That in itself would be unprecedented, as short cycles in the past have always accompanied very active solar maximums, not weak maximums like the maximum we have just seen.

I still expect the ramp down to solar minimum to slow down and stretch out to 2019, as would be more normal, but I also would not bet any money on this expectation, at this point.

The big question remains: Will the solar cycle continue as normal after this upcoming solar minimum, or will we instead see our first grand minimum since the Maunder Minimum in the 1600s, a period lasting for about a century with no obvious sunspots that also corresponded to the Little Ice Age?

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Solar storm activates global aurora on Mars

12:00 pm

The strong solar flare that occurred earlier this month was strong enough to activate a global aurora on Mars.

The solar event on Sept. 11, 2017 sparked a global aurora at Mars more than 25 times brighter than any previously seen by the MAVEN orbiter, which has been studying the Martian atmosphere’s interaction with the solar wind since 2014. It produced radiation levels on the surface more than double any previously measured by the Curiosity rover’s Radiation Assessment Detector, or RAD, since that mission’s landing in 2012. The high readings lasted more than two days.

Strangely, it occurred in conjunction with a spate of solar activity during what is usually a quiet period in the Sun’s 11-year sunspot and storm-activity cycle. This event was big enough to be detected at Earth too, even though Earth was on the opposite side of the Sun from Mars.

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Sunspot update for August 2017

10:52 am

Yesterday NOAA posted its monthly update of the solar cycle, covering sunspot activity for August. That graph is posted below, with annotations.

August 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The long slow decline to solar minimum has now shown itself. Up until now, the ramp down from solar maximum had been fast and steep, unlike past solar cycles where the ramp down is slow and steady. The last few months the ramp down had practically ceased. In this August graph the ramp down turned into a temporary ramp up. Considering the strong activity going on right now as well as the past week, I expect the September numbers to also show this increase.

None of this means that the ramp down has ended, or that we will not see a solar minimum. All it means is that it takes awhile for the Sun to slowly calm down after each solar maximum. The sunspots we are seeing right now, all near the equator, are from the solar cycle now slowly ending. We will know the minimum is coming as well as the next solar maximum when the first tiny and rare sunspots appear in high latitudes. These high latitude sunspots will belong to the next cycle, and will have reversed polarity.

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Ten planetary probes track a solar eruption through the solar system

9:02 am

The path of an October 2014 solar eruption was tracked by ten different spacecraft, including Curiosity on the surface of Mars, as its blast moved outward through the solar system.

The measurements give an indication of the speed and direction of travel of the CME [Coronal Mass Ejection], which spread out over an angle of at least 116 degrees to reach Venus Express and STEREO-A on the eastern flank, and the spacecraft at Mars and Comet 67P Churyumov–Gerasimenko on the western flank.

From an initial maximum of about 1000 kilometers per second (621 miles per second) estimated at the sun, a strong drop to 647 kilometers per second (402 miles per second) was measured by Mars Express three days later, falling further to 550 kilometers per second (342 miles per second) at Rosetta after five days. This was followed by a more gradual decrease to 450–500 kilometers per second (280-311 miles per second) at the distance of Saturn a month since the event.

The CME was first detected by solar observatories Proba-2, SOHO, Solar Dynamics Observatory, and STEREO-A.It was then tracked as it moved outward by Venus Express, Mars Express, MAVEN, Mars Odyssey, Curiosity, Rosetta, Cassini, and even New Horizons and Voyager 2.

On my last appearance on Coast to Coast, I was specifically asked if the probes to Venus, Mars, and other planets have the capability to track solar events. I knew that the Voyager spacecraft had equipment to do this, but was unsure about other planetary probes. This article answers that question.

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Sun’s core rotates 4X faster than surface

8:24 am

The uncertainties of science: Scientists have discovered that the core of the Sun rotates four times faster than its surface layers.

The rotation of the solar core may give a clue to how the sun formed. After the sun formed, the solar wind likely slowed the rotation of the outer part of the sun, he said. The rotation might also impact sunspots, which also rotate, Ulrich said. Sunspots can be enormous; a single sunspot can even be larger than the Earth.

The researchers studied surface acoustic waves in the sun’s atmosphere, some of which penetrate to the sun’s core, where they interact with gravity waves that have a sloshing motion similar to how water would move in a half-filled tanker truck driving on a curvy mountain road. From those observations, they detected the sloshing motions of the solar core. By carefully measuring the acoustic waves, the researchers precisely determined the time it takes an acoustic wave to travel from the surface to the center of the sun and back again. That travel time turns out to be influenced a slight amount by the sloshing motion of the gravity waves, Ulrich said.

This phenomenon had been predicted more than twenty years ago, but never observed until now.

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New data suggests Sun undergoing fundamental changes

8:40 am

The uncertainty of science: New data, when compared with similar data collected over decades, suggests the Sun’s solar cycle is undergoing some fundamental changes.

In work just published in the Monthly Notices of the Royal Astronomical Society, the team shows that the interior of the Sun has changed in recent years, and that these changes persist in the current cycle. In combination with theoretical models, the observations suggest that the magnetic field distribution in the outer layers may have become a bit thinner. Other seismic data shows that the rotation rate of the Sun has also undergone some changes in the way the Sun rotates at different latitudes.

“Again, this is not how it used to be and the rotation rate has slowed a bit at latitudes around about 60 degrees. We are not quite sure what the consequences of this will be but it’s clear that we are in unusual times. However, we are beginning to detect some features belonging to the next cycle and we can suggest that the next minimum will be in about two years,” says Elsworth.

First, they don’t know what will happen because of these changes. Second, their data confirms that the solar minimum will occur in about two years, which would make this cycle only 9 years long, one of the shortest but also one of the weakest that has been observed, two things that previously had never gone together.

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Sunspot update for June 2017

11:47 am

Today NOAA posted its monthly update of the solar cycle, covering sunspot activity for June. As I have done every month since 2010, the graph is posted below, with annotations.

June 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Sunspot activity in June was almost exactly the same as in May, and thus continued the overall downward trend that is below the 2007 low prediction and that suggests that this very weak solar maximum will end much earlier than predicted, and will make it an unprecedented short but weak cycle. The Sun is once again blank today for the first time in about two weeks, repeating the pattern we have seen for several months where, because one hemisphere of the Sun is blank while the other hemisphere has some sunspots, the rise and fall of the sunspot counts tracks the 27-day solar rotation almost precisely.

There continues to be evidence that the Sun is undergoing significant changes this solar cycle, all of which are pointing to the possibility that a grand minimum is coming, with no sunspots for decades. And as I have said now monthly for six years, past grand minimums have consistently occurred at the same time the Earth’s climate has cooled. The scientific link remains unclear, but if we should undergo a grand minimum in the coming decades, we will finally have the opportunity to find out what that link is.

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Sunspot update for May 2017

10:32 am

Last week NOAA posted its monthly update of the solar cycle, covering sunspot activity for May. Unfortunately, there appeared to be a problem with their posting software. Though the date of the image changed, the graph itself was not updated. I contacted NOAA, and Ann Newman, IT Specialist at NOAA’s
Space Weather Prediction Center, took a look and quickly fixed the problem.

The corrected graph is posted below, with annotations, as I have done now every month since 2010.

May 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The decline in sunspot activity resumed in May, putting the trend back below the 2007 low prediction. Overall, the trend continues to suggest that this very weak solar maximum will end much earlier than predicted, and will make it an unprecedented short but weak cycle. As the Sun is at this moment blank, and has been for several days, I expect that June will end up with low numbers as well, continuing this trend.

As I have repeatedly said now monthly for six years, if history is any guide, the Sun’s low activity should correspond with cooler temperatures here on Earth. Why this happens is not yet understood, though there are theories.

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NASA names next solar mission after pioneer solar scientist Eugene Parker

10:31 pm

NASA has named its next solar mission, which will fly closer to the Sun than any previous mission, after pioneer solar scientist Eugene Parker, who in the 1950s predicted the existence of the solar wind.

The new moniker honors pioneering University of Chicago astrophysicist Eugene Parker, who predicted the existence of the solar wind — the stream of charged particles flowing constantly from the sun — back in 1958. [Solar Quiz: How Well Do You Know Our Sun?]

NASA has named about 20 space missions after people; the Hubble Space Telescope is perhaps the most famous example. But the 89-year-old Parker is the first researcher to be celebrated in this manner while still alive, agency officials said.

Parker deserves it, for sure, and it is really nice to honor him while he is still alive to appreciate it.

The spacecraft is scheduled to launch at the end of July.

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Sunspot update for April 2017

3:53 pm

Today NOAA posted its monthly update of the solar cycle, covering sunspot activity for April. It is posted below, with annotations, as I have done now every month since 2010.

April 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

April showed an uptick in sunspot activity, enough to move the numbers back up above the 2007 low prediction. Nonetheless, activity as the cycle has been ramping down has consistently and generally remained below expectation, and does seem heading to an early arrival of solar minimum, sometime in late 2019 or early 2020, about a year early.

I don’t want to sound like a broken record, as I have written this practically every month since I started these updates in 2010, but this short and weak solar maximum suggests the possibility that we might be facing a grand minimum, where there are no significant sunspots for decades. Some solar scientists think this is coming. Others are much more doubtful. Regardless, we can only wait and watch, while also recognizing that weak solar maximums and grand minimums have in the past consistently coincided with global cool weather. The reasons why this has happened are not yet known, but it has happened nonetheless.

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Sunspot update for March 2017

11:32 am

On April 3, while I was in the Grand Canyon, NOAA posted its monthly update of the solar cycle, covering sunspot activity for March. As I have been doing every month since 2010, I am posting it here with annotations to give it context.

March 2017 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

The decline in sunspots continues to run below predictions, suggesting an end to this solar cycle and a solar minimum as early as sometime in 2018. And as I noted in my February update, sunspot activity continues to track the Sun’s 27 day rotation, alternating every two weeks between blank and active hemispheres. We had the longest stretch, more than two weeks, without sunspots in March. This was followed by about two weeks of activity, followed by several blank days and a relatively inactive Sun at present, beginning a little less than a week ago. I expect this period of inactivity to last another ten days or so, and then things will pick up again.

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